The present invention relates to train handling techniques and more specifically to the analysis of train handling techniques.
Training systems for locomotive engineers have been well known. A Train Dynamic Analyzer (TDA) is such a training system offered by the Train Dynamic Service Group of New York Air Brake Corporation.
The TDA functionality was enhanced to assist in training the Locomotive Engineer how to better handle their trains. Designs of simulators with math models are shown in U.S. Pat. Nos. 4,041,283; 4,827,438 and 4,853,883. Further capability was added to investigate accidents by playing the event recorder data through the TDA and monitoring critical physical parameters. Through the years, data was collected from instrumented trains and laboratory experiments, allowing the models used by the TDA to be refined. On board data collection for off-loading is shown in U.S. Pat. Nos. 4,561,057 and 4,794,548.
As more Locomotive Engineers became familiar with the TDA display through training sessions, it became apparent that a real time version of the TDA in the cab of a locomotive would offer substantial benefits in improved train handling. Improved train handling would in turn foster safety and economic benefits. Earlier designs for on board computer controllers is shown in U.S. Pat. No. 4,042,810 with a description of math models.
A more advanced version of the TDA for real time on-board display and control is the LEADER system, also available from the Train Dynamic Service Group of New York Air Brake Corporation.
The LEADER system has all the necessary information to predict the future state of the train given a range of future command changes (what if scenarios). With this ability, LEADER system can assist the railroads in identifying and implementing a desired operating goal; minimize time to destination, maximize fuel efficiency, minimize in train forces, (etc.) or a weighted combination thereof. LEADER system will perform calculations based on the operational goal and the current state of the train to make recommendations to the Locomotive Crew on what operating changes will best achieve these goals.
The LEADER system provides safe and effective control of a train through display or control of the dynamically changing parameters. It accurately provides train speed within designated speed limits. It maintains in-train coupling forces with safe limits to prevent train break-in-twos. It maintains safe levels of lateral forces between the wheels and the rails of all cars to prevent cars from departing from the track and derailing. It provides control of slack (draft) action or shock (buff) between cars to reduce damage to valuable lading and to prevent potential train separation or break-in-twos. It maintains train stops and slow downs to prevent the train from entering unauthorized territories that could cause accidents with other train traffic or work crews. It determines the optimum locomotive throttle setting and train brake application to minimize fuel consumption and wear of brake shoes and wheels. It monitors total locomotive performance, train brake performance and it provides advisement if performance is faulty. It forecasts the estimate time of arrival of train to various switch points, signals locations or final destinations to advise the engineer and rail traffic control centers. It records various key data for later downloaded analysis for operational studies and accident investigations as well as engineer qualifications.
The systems to date, including the LEADER system, attempt to analyze the performance of a operator's train handling techniques against a standard run, but do not take into account various operating constraints which occur during the run that differ from that which are part of the standard operating restraints. During the run, there may be a meet and pass order issued, order to the sidings for a stop issue as well as various changes in traffic signal designations. Also, standard operating conditions which are generally preset during a run may change during the run. These may include standing slow orders, track occupancy permits, speed restriction zones and general operating bulletins.
The present invention is a method of analyzing train handling by setting a standard run for a territory by collecting actual train operating data from a run across the territory and determining operating constraints during the run which are not included in the standard. The determination of operating constraints during a run also includes determining differences between the operating constraints during the run of those included in the standard. The train handling data is compared to the standard and the comparison is adjusted for the operating constraints. The adjustment of the comparison includes nullifying any deviation of the handling data from the standard resulting from the operating constraints. This modification includes substituting the operating data for the standard data for that section of the run in which the operating constraints occur. The boundaries of the section of the run is defined by one or more of the following handling data: speed, acceleration/deacceleration, slack action, propulsion settings, brake settings and position. All boundary conditions are met when performing the substitution.
The standard is set by determining operating practices which include one or more of speed limits, run-in/run-out force limitations and steady state draft and buff forces. This standard set also includes determining equipment limitations which includes one or more of time constants for change of tractive effort, time constants for change in dynamic braking and time constants for changing pneumatic braking. The standard includes one or more of the following operating restraints: standing slow orders, track occupancy permits, speed restriction zones and general operating bulletins. The operating constraints determined during the run includes one or more of meet and pass orders, traffic signal designation and order to sidings for a stop. The standard is set by weighting one or more of fuel usage, in-train forces and run duration. The standard is set and includes taking advantage of rail topology of the run in the use of braking and propulsion. The topology includes rail grade and curvature.
A report is created from the standard and the handling data correlating the energy usage for specific categories. These categories include one or more of pneumatic braking, dynamic braking and track topology. The report further includes energy modifications for the operating constraints determined during the run. The operating conditions not taken into account in the standard include stop and slow down orders. The report for pneumatic and dynamic braking includes energy for the following subcategories: slow downs, balancing grade and power braking. The energy determined and reported for track topology includes energy for curve resistance, grade resistance and rolling resistance.
Other advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.